We’ve released a small security patch that corrects a file upload validation issue.  This problem only affects file uploads from within the EE control panel (where users must have access and other permissions), so while it is not a serious concern for most sites, all ExpressionEngine users are encouraged to update their files.

If your site is currently running ExpressionEngine 1.5.2, then we suggest you download the most recent build of ExpressionEngine from our download area and update your site following the build update instructions.

If you wish to update just the modified file, then we have provided a stand alone patch for the following listed versions.  If you are using a version of ExpressionEngine previous to these, then you must upgrade your site by following the instructions for updating to the most recent version.

- Modified core.upload.php for ExpressionEngine 1.5.2
- Modified core.upload.php for ExpressionEngine 1.5.1
- Modified core.upload.php for ExpressionEngine 1.5.0

* Thanks goes to one of our users who contacted us privately during the weekend and allowed us to confirm the validation problem and create a patch before notifying our community.  Kudos.